textproduct: Albany

WHAT HAS CHANGED

Dropped overnight lows slightly from the previous forecast and added patchy fog. Main focus was on the rainfall tomorrow into Tuesday. Starting to see a better consensus for a more northern storm track and northward shift in the axis of heaviest qpf relative to the previous forecast. Will also mention heavier rainfall rates possible given further northward extend of the elevated instability.

KEY MESSAGES

1) High confidence for a widespread soaking rainfall across eastern NY/western New England Mon into Tue morning. This will be a largely beneficial rainfall for most areas, although isolated minor flooding in urban/poor drainage areas is possible.

DISCUSSION

KEY MESSAGE 1...Tomorrow an upper shortwave will track through the Ohio Valley, around the periphery of an upper low located north of the Great Lakes. At the sfc, an associated area of low pressure will track along a stalled frontal boundary to our south, and will help lift this boundary north as a warm front as the sfc low approaches from the southwest. A strengthening S/SW LLJ will aid in moisture transport into our region, with PWATs expected to climb to 1.6-1.8" (highest for southern areas) per the latest HREF. Isentropic lift over the sloping warm front, a band of mid-level FGEN, and the right entrance of an upper jet streak will provide fairly strong forcing for ascent, which will result in widespread showers/areas of rain overspreading the region from mid-morning into early afternoon. Rain continues through Monday night before tapering off Tuesday morning from west to east.

While there still remains more spread in the guidance that we'd like to see at this juncture, we are are least starting to see a better consensus with the 12z guidance as the more northern NAM/RGEM have come back south, while other sources of guidance have shifted further north. This middle ground solution would shift the axis of heaviest rainfall further north from previous forecasts, placing it from around the Schoharie Valley through the Capital District and into southern VT. Should this solution pan out, a tongue of elevated instability would be able to reach up to around the Capital District. This could result in some heavier rainfall rates (up to 1- 1.5" per hour) for areas around the Capital District and points south. Total rainfall amounts will likely be a widespread 0.5 to 1.5" with localized areas up to 2-3" wherever the axis of heaviest rainfall sets up.

WPC has indicated that they plan to keep the marginal ERO across much of our areas outside of the ADKs, which aligns with our current thinking. Will continue the message that this will by and large be a very beneficial rainfall for most of the region, with areas south of I-90 in D0 to D1 drought based on the latest drought monitor. That said, some nuisance ponding of water in the typical urban and poor drainage areas will be possible. Fast flow aloft should reduce the flash flood potential, but an isolated flash flood can't be ruled out if we see convective elements with heavier rainfall rates repeatedly training over any of the more urban areas. The best chance for this, again, appears to have shifted further north, over the Capital District. This is where the best overlap of moisture, instability, and FGEN is expected near or just north of the 850 mb warm front. Finally, will mention that with the shift north in the storm track, SPC has expanded the marginal risk for severe weather (main hazard would be isolated gusty winds) into the Mid Hudson Valley. Overall, though, severe threat is less of a focus than that for locally heavy rain.

As the system pulls away to the east Tuesday, its cold front will track through the region, resulting in lower humidity for Wednesday, although temperatures will actually be warmer 70s to low 80s Tuesday and Wednesday with less cloud cover. Wednesday looks dry with flow aloft becoming more zonal as heights rise aloft and an area of high pressure builds towards our area. While the current deterministic forecast shows chances for showers Thursday, this is likely due in part to the NBM fast bias - Thursday looks mainly dry for eastern areas, with some scattered showers/storms possible later in the day for western areas. Friday is expected to have a better chance for some showers or thunderstorms as another upper shortwave or upper low tracks north of our area with the associated sfc low dragging a cold front through our region by Saturday. Temperatures for the second half of the week are expected to reach the low to possibly mid 80s for valley areas, which is near normal for this time of year, but humidity will begin to increase Thursday and especially Friday.

AVIATION /00Z MONDAY THROUGH FRIDAY/

Through 00Z Tuesday... VFR conditions prevail through at least 06 UTC; however, clear skies following a few afternoon showers will likely allow fog to form once again at GFL and even PSF. We maintained the TEMPO group from the previous TAF issuance from 07/08 UTC to 10 UTC both sites for IFR and MVFR vis, respectively. However, an increasing cirrus canopy towards 10 - 12 UTC should make the fog short-lived. Clouds thicken and gradually lower across all terminals 12 - 15 UTC before initial areas of showers arrive 15 - 18 UTC. However, ceilings likely remain VFR with potential for MVFR vis. Rain turns steady/widespread by 18 - 19 UTC across all terminals resulting in MVFR and even intermittent IFR vis by 21 - 23 UTC as rain becomes heavy at times. There is low chance for isolated thunder mainly at PSF and POU but given low confidence, did not include in the latest update.

Light and variable across all terminals tonight. Then, southerly winds around 5kts develop by 15 - 18 UTC before shifting east- northeasterly around 18 UTC. Sustained winds become 5 - 10kts with gusts up to 15kts. Low-level wind shear may need to be added in the next update towards the end of the TAF period as the 30-35kt low-level jet develops at 2kft.

Outlook...

Monday Night: High Operational Impact. Definite SHRA. Tuesday: Low Operational Impact. NO SIG WX. Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: No Operational Impact. NO SIG WX. Wednesday Night: No Operational Impact. NO SIG WX. Thursday: Moderate Operational Impact. Chance of SHRA...TSRA. Thursday Night: High Operational Impact. Definite SHRA...TSRA. Friday: High Operational Impact. Definite SHRA...TSRA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.